One Direction's Zayn Malik: We didn't realise how crazy America would be until we got to US
One Direction had no idea how popular they were in the US before they arrived there to tour with Big Time Rush.
The boys received thousands of Twitter messages before they set off across the Atlantic but were sure they'd been sent by a small number of loyal American fans.
'We thought it could be the same few hundred people Tweeting us over and over again,' Zayn Malik, 19, tells The Sun.
'Until we got to America we didn't realise how crazy it was.'
1D reached No 28 on the Billboard Singles Hot 100 with Brit Award-winning single What Makes You Beautiful and their debut album Up All Night shot to No 1 on the US iTunes charts.
The lads are thrilled at their success over the pond.
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